EP0051815B2

EP0051815B2 - Pump comprising locking means for a flexible tube

Info

Publication number: EP0051815B2
Application number: EP81109187A
Authority: EP
Inventors: Kaj Ove Stenberg; Lars Harald Nyström
Original assignee: Gambro Lundia AB
Current assignee: Gambro Lundia AB
Priority date: 1980-11-06
Filing date: 1981-10-29
Publication date: 1990-02-28
Anticipated expiration: 2001-10-29
Also published as: ATE6167T1; JPS57108489A; DK150945C; US4412793A; SE439041B; DK487881A; SE8007803L; DK150945B; EP0051815A1; EP0051815B1; IE52158B1; DE3162182D1; IE812542L

Abstract

Pump comprising a flexible tube (8) arranged in a path between an inlet (10) and an outlet (11), and means for locking said tube at said inlet and outlet. Said means comprises moveably adjustable organs (12 and 13) being adapted to lock said tube against seats (14 and 15) at said inlet and outlet. <??>Preferably, each of said moveable organs is in the form of slides having a cup-shaped surface (22, 23) provided with an extended lower edge (24, 25) in the direction of movement of the associated slide. Correspondingly, each of said seats (14 and 15) is preferably also provided with a cup-shaped surface (26, 27) facing said tube. <??>Especially, the respective slide can be provided at the respective end of a common rod (18), preferably through threading, whereby the movement of said slides is provided through rotation of the rod by means of a centrally located wheel (19).

Description

Technical Field

This invention relates to a pump comprising a flexible tube arranged in a path between an inlet and an outlet of said pump, and means including adjustable organs which are movable in opposite directions to each other for locking of said tube against corresponding seats at said inlet and outlet, respectively.
More precisely, the invention is concerned with an improved locking means for locking a flexible tube in connection with heart/lung machine pumps.

Background of the Invention

In known devices of the kind described above the tube is usually locked by means of especially designed inserts which are adapted to lock the tube against a seat at the inlet and outlet, respectively. Usually such inserts are mounted on the pump by means of some form of screw joint and dimensioned such that they fit only one tube dimension at a time.
A serious drawback to these known inserts is consequently that they necessarily must be exchanged in connection with a change of tube dimension. Such an exchange is not only time- consuming, but requires furthermore that some sort of tool is used to loosen the screw joint. Especially troublesome are therefore such exchanges in connection with heart/lung machine pumps where one often has to change tube dimensions in dependency on desired range of flow.
One important difference between our present device and a known device according to US-A-3 138 104 is that the movably adjustable organs of our device are movable simultaneously in opposite directions to each other to lock the tube against the opposing seats at the inlet and the outlet, while the corresponding movably adjustable organs 64, 66 of the known device are movable simultaneously in same directions to lock the tube 32 against nonopposing seats.
This difference between our device and the known device offers the advantage over the prior art that we can make a more rapid and easy exchange of tubes, since we need only loosen the organs from the tube ends without removing the entire locking means from the pump.
It is not only more complicated to exchange tubes with the known device, but it takes also more time to do this. This is a serious disadvantage in case the pump is used in a socalled heartlung machine where temporarily disruptions of blood flow through the tube can be critical to the patient undergoing surgery.
The known device according to FR-A-2 321 147 includes only details which are similar to corresponding details of our present device, but differs basically from our device since this known device does not include simultaneously mowable organs for locking the tube at the inlet and the outlet of the pump. According to the FR-A-2 321 147 such locking organs 6, 6 (see for example Fig. 1 ) are not simultaneously operable but must be moved separately by means of separate thumb screws 5, 5. Consequently, a tube exchange in this known device is more complicated and takes also a longer time than a corresponding tube exchange in our present device, since one has to consecutively loosen the locking organs 6, 6 in this known device. According to our present device this can be done in one step and simultaneously.
One object of the present invention is therefore to provide a pump which neither requires exchange of inserts nor use of special tools in connection with a change of tube dimensions.
A further object of the invention is to facilitate tube exchange by providing a simple but anyhow reliable tube locking means by means of which a tube may be quickly locked to or released from a pair of tube locking seats.

Description of the Invention

According to the present invention there is provided a pump of the kind as described in the preamble of claim 1. Said pump is characterized in that said movable organs are controlled by means of a common control means to lock said tube simultaneously against said seats at said inlet and said outlet, respectively which mowable organs (12, 13) are provided in the form of two threaded slides of the threaded ends (16, 17) of a common rod (18) controlled by said common control means (19)
Said organs are provided at the respective end of a common rod, whereby it is possible to lock the tube simultaneously at said inlet and said outlet. Said organs are mounted at said respective end of the rod through screw threading, whereby the movement of these organs can easily be achieved by rotating the rod.
According to an especially preferred embodiment said organs are in the form of slides, each having a cup-shaped surface facing the tube to evenly surround the tube upon the locking thereof. Conveniently, the respective seat has also a corresponding cup-shaped side facing the tube, whereby the whole tube is surrounded in connection with said locking thereof.
Preferably, the cup-shaped surface of each slide is provided with an extended lower edge in the direction of movement of the slide, whereby the tube will be guided towards the corresponding cup-shaped side of the associated seat. This is especially advantageous in connection with small tube dimensions.

Brief Description of the Drawings

The present invention will be described more in detail in the following with reference to the accompanying drawings, wherein

Fig. 1 is a front view of a preferred embodiment of the pump according to the present invention,
Fig. 2 is an elevation view of the pump in Fig. 1, having its lid in open position, and
Fig. 3 is a schematic view of an especially preferred embodiment of the locking means for locking the tube in the pump in Figs. 1 and 2.

Detailed Description of the Invention

As shown in Figs. 1 and 2 the pump according to the present invention may conveniently be housed in an essentially rectangular box 1 comprising a cup-shaped bottom portion 2 and to an openable and closable lid 3.
Preferably, said lid 3 has a central opening 4 which may be covered by for example a transparent plastic cover 5, whereby it is possible to supervise the pump without the need to open the lid.
Centrally located in the cup-shaped bottom portion 2 is a rotatable rotor 6 comprising for example two or more circumferentially located rollers 7a. 7b. Said rollers are adapted to compress the tube 8 against the inner wall 9 of the cup-shaped bottom portion to pump for example a liquid contained in the tube from inlet 10 to outlet 11.
According to the present invention said pump comprises thus a flexible tube 8 which is arranged in a path between said inlet 10 and said outlet 11, and locking means to lock the tube at said inlet and outlet, respectively.
As suggested in Figs. 1 and 2 said means comprises two mowable organs 12 and 13 in the form of slides which are adapted to alternately move towards and from, respectively, a seat 14 and 15, respectively at said inlet 10 and said outlet 11, as will be described in more detail with reference to Fig. 3.
In Fig. 3 there is shown an especially preferred embodiment of said locking means for locking the tube in for example the pump as shown in Figs. 1 and 2. According to this embodiment said slides 12 and 13 are mounted at the respective end 16 and 17 of a common rod 18 and being mowable towards and from, respectively, said seats 14 and 15 for the tube 8 by rotation of the rod 18 by means of a centrally located wheel 19.
As suggested in Fig. 3 by broken lines each of said slides 12 and 13 are provided with an internally threaded seat 20, 21 for receiving of a corresponding threaded end 16 and 17, respectively, of the rod 18. If, for example the one end 16 of the rod is clockwisely threaded and the other end 17 is anticlockwisely threaded the slides 12 and 13 thereby will simultaneously move either towards or from the respective seats
14 and 15 for locking and releasing, respectively, the tube 8 at the inlet 10 and outlet 11.
From Fig. 3 it can furthermore be seen that the respective surfaces 22 and 23 of the slides 12 and 13, which are facing the tube 8, are cup-shaped, whereby each of said cup-shaped surfaces has an extended lower edge 24 and 25, respectively, to lift and guide the tube 8 towards the corresponding cup-shaped sides 26 and 27 of the seat 14 and 15, respectively.
The rotor 6 shown in Figs. 1 and 2 is preferably rotated by means of a motor (not shown) via a drive shaft (not shown) which is received in the bottom portion of the rotor through a suitable bearing.

Industrial Applicability

The pump according to the present invention is especially adapted to be used in connection with heart/lung machines, but is also suitable in other applications where it is often needed to change tube dimensions in dependency on the desired flow range,

Claims

1. Pump which comprises a flexible tube (8) arranged in a path between an inlet (10) and an outlet (11) of said pump, and means (12, 13, 18, 19) including adjustable organs (12, 13) in opposite directions to each other which are movable for locking of said tube against corresponding seats (14, 15) at said inlet and outlet, respectively, characterized in that said mowable organs (12, 13) are controlled by means of a common control means (19) to lock said tube (a) simultaneously against said seats (14, 15) at said inlet (10) and said out let (11), respectively, which mowable organs (12, 13) are provided in the form of two threaded slides at the threaded ends (16, 17) of a common rod (18) controlled by said common control means (19).

2. Pump in accordance with claim 1, characterized in that each of said slides (12, 13) has a cup-shaped surface (22, 23) facing said tube (8).

3. Pump in accordance with any one of the preceding claims, characterized in that each of said seats (14, 15) has a cup-shaped surface (26, 27) facing said tube (8).

4. Pump in accordance with claim 2 or 3, characterized in that each of the cup-shaped surfaces (22, 23) of the respective slide (12, 13) is provided with an extended lower edge in the direction of movement of the associated slide.